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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E26">Th23</font></span>: <a NAME="T23"><span class="comment"><font color="firebrick">:: NAT_6:23</font></span><br/></a><div class="add">2 <a href="nat_6.html#NR1" title="NAT_6:NR.1">is_quadratic_non_residue_mod</a> 3</div></div>
